Electro-kinetic air transporter-conditioner

ABSTRACT

An electro-kinetic electro-static air conditioner includes a self-contained ion generator that provides electro-kinetically moved air with ions and safe amounts of ozone. The ion generator includes a high voltage pulse generator whose output pulses are coupled between first and second electrode arrays. Preferably the first array comprises one or more wire electrodes spaced staggeringly apart from a second array comprising hollow “U”-shaped electrodes. Preferably a ratio between effective area of an electrode in the second array compared to effective area of an electrode in the first array exceeds about 15:1 and preferably is about 20:1. An electric field produced by the high voltage pulses between the arrays produces an electrostatic flow of ionized air containing safe amounts of ozone. A bias electrode, electrically coupled to the second array electrodes, affects net polarity of ions generated. The outflow of ionized air and ozone is thus conditioned.

This is a continuation of application Ser. No. 09/186,471 filed Nov. 5,1998 now U.S. Pat. No. 6,176,977.

FIELD OF THE INVENTION

This invention relates to electro-kinetic conversion of electricalenergy into fluid flow of an ionizable dielectric medium, and morespecifically to methods and devices for electro-kinetically producing aflow of air from which particulate matter has been substantiallyremoved. Preferably the air flow should contain safe amounts of ozone(O₃).

BACKGROUND OF THE INVENTION

The use of an electric motor to rotate a fan blade to create an air flowhas long been known in the art. Unfortunately, such fans producesubstantial noise, and can present a hazard to children who may betempted to poke a finger or a pencil into the moving fan blade. Althoughsuch fans can produce substantial air flow, e.g., 1,000 ft³/minute ormore, substantial electrical power is required to operate the motor, andessentially no conditioning of the flowing air occurs.

It is known to provide such fans with a HEPA-compliant filter element toremove particulate matter larger than perhaps 0.3 μm. Unfortunately, theresistance to air flow presented by the filter element may requiredoubling the electric motor size to maintain a desired level of airflow.Further, HEPA-compliant filter elements are expensive, and can representa substantial portion of the sale price of a HEPA-compliant filter-fanunit. While such filter-fan units can condition the air by removinglarge particles, particulate matter small enough to pass through thefilter element is not removed, including bacteria, for example.

It is also known in the art to produce an air flow using electro-kinetictechniques, by which electrical power is directly converted into a flowof air without mechanically moving components. One such system isdescribed in U.S. Pat. No. 4,789,801 to Lee (1988), depicted herein insimplified form as FIGS. 1A and 1B. Lee's system 10 includes an array ofsmall area (“minisectional”) electrodes 20 that is spaced-apartsymmetrically from an array of larger area (“maxisectional”) electrodes30. The positive terminal of a pulse generator 40 that outputs a trainof high voltage pulses (e.g., 0 to perhaps +5 KV) is coupled to theminisectional array, and the negative pulse generator terminal iscoupled to the maxisectional array.

The high voltage pulses ionize the air between the arrays, and an airflow 50 from the minisectional array toward the maxisectional arrayresults, without requiring any moving parts. Particulate matter 60 inthe air is entrained within the airflow 50 and also moves towards themaxisectional electrodes 30. Much of the particulate matter iselectrostatically attracted to the surface of the maxisectionalelectrode array, where it remains, thus conditioning the flow of airexiting system 10. Further, the high voltage field present between theelectrode arrays can release ozone into the ambient environment, whichappears to destroy or at least alter whatever is entrained in theairflow, including for example, bacteria.

In the embodiment of FIG. 1A, minisectional electrodes 20 are circularin cross-section, having a diameter of about 0.003″ (0.08 mm), whereasthe maxisectional electrodes 30 are substantially larger in area anddefine a “teardrop” shape in cross-section. The ratio of cross-sectionalareas between the maxisectional and minisectional electrodes is notexplicitly stated, but from Lee's figures appears to exceed 10:1. Asshown in FIG. 1A herein, the bulbous front surfaces of the maxisectionalelectrodes face the minisectional electrodes, and the somewhat sharptrailing edges face the exit direction of the air flow. The “sharpened”trailing edges on the maxisectional electrodes apparently promote goodelectrostatic attachment of particulate matter entrained in the airflow.Lee does not disclose how the teardrop shaped maxisectional electrodesare fabricated, but presumably they are produced using a relativelyexpensive mold-casting or an extrusion process.

In another embodiment shown herein as FIG. 1B, Lee's maxisectionalsectional electrodes 30 are symmetrical and elongated in cross-section.The elongated trailing edges on the maxisectional electrodes provideincreased area upon which particulate matter entrained in the airflowcan attach. Lee states that precipitation efficiency and desiredreduction of anion release into the environment can result fromincluding a passive third array of electrodes 70. Understandably,increasing efficiency by adding a third array of electrodes willcontribute to the cost of manufacturing and maintaining the resultantsystem.

While the electrostatic techniques disclosed by Lee are advantageous toconventional electric fan-filter units, Lee's maxisectional electrodesare relatively expensive to fabricate. Further, increased filterefficiency beyond what Lee's embodiments can produce would beadvantageous, especially without including a third array of electrodes.

Thus, there is a need for an electro-kinetic air transporter-conditionerthat provides improved efficiency over Lee-type systems, withoutrequiring expensive production techniques to fabricate the electrodes.Preferably such a conditioner should function efficiently withoutrequiring a third array of electrodes. Further, such a conditionershould permit user-selection of safe amounts of ozone to be generated,for example to remove odor from the ambient environment.

The present invention provides a method and apparatus forelectro-kinetically transporting and conditioning air.

SUMMARY OF THE PRESENT INVENTION

The present invention provides an electro-kinetic system fortransporting and conditioning air without moving parts. The air isconditioned in the sense that it is ionized and contains safe amounts ofozone.

Applicants' electro-kinetic air transporter-conditioner includes alouvered or grilled body that houses an ionizer unit. The ionizer unitincludes a high voltage DC inverter that boosts common 110 VAC to highvoltage, and a generator that receives the high voltage DC and outputshigh voltage pulses of perhaps 10 KV peak-to-peak, although anessentially 100% duty cycle (e.g., high voltage DC) output could be usedinstead of pulses. The unit also includes an electrode assembly unitcomprising first and second spaced-apart arrays of conductingelectrodes, the first array and second array being coupled,respectively, preferably to the positive and negative output ports ofthe high voltage generator.

The electrode assembly preferably is formed using first and secondarrays of readily manufacturable electrode types. In one embodiment, thefirst array comprises wire-like electrodes and the second arraycomprises “U”-shaped electrodes having one or two trailing surfaces. Inan even more efficient embodiment, the first array includes at least onepin or cone-like electrode and the second array is an annularwasher-like electrode. The electrode assembly may comprise variouscombinations of the described first and second array electrodes. In thevarious embodiments, the ratio between effective area of the secondarray electrodes to the first array electrodes is at least about 20:1.

The high voltage pulses create an electric field between the first andsecond electrode arrays. This field produces an electro-kinetic airflowgoing from the first array toward the second array, the airflow beingrich in preferably a net surplus of negative ions and in ozone. Ambientair including dust particles and other undesired components (germs,perhaps) enter the housing through the grill or louver openings, andionized clean air (with ozone) exits through openings on the downstreamside of the housing.

The dust and other particulate matter attaches electrostatically to thesecond array (or collector) electrodes, and the output air issubstantially clean of such particulate matter. Further, ozone generatedby the present invention can kill certain types of germs and the like,and also eliminates odors in the output air. Preferably the transporteroperates in periodic bursts, and a control permits the user totemporarily increase the high voltage pulse generator output, e.g., tomore rapidly eliminate odors in the environment.

Other features and advantages of the invention will appear from thefollowing description in which the preferred embodiments have been setforth in detail, in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plan, cross-sectional view, of a first embodiment of aprior art electro-kinetic air transporter-conditioner system, accordingto the prior art;

FIG. 1B is a plan, cross-sectional view, of a second embodiment of aprior art electro-kinetic air transporter-conditioner system, accordingto the prior art;

FIG. 2A is a perspective view of a preferred embodiment of the presentinvention;

FIG. 2B is a perspective view of the embodiment of FIG. 2A, with theelectrode assembly partially withdrawn, according to the presentinvention;

FIG. 3 is an electrical block diagram of the present invention;

FIG. 4A is a perspective block diagram showing a first embodiment for anelectrode assembly, according to the present invention;

FIG. 4B is a plan block diagram of the embodiment of FIG. 4A;

FIG. 4C is a perspective block diagram showing a second embodiment foran electrode assembly, according to the present invention;

FIG. 4D is a plan block diagram of a modified version of the embodimentof FIG. 4C;

FIG. 4E is a perspective block diagram showing a third embodiment for anelectrode assembly, according to the present invention;

FIG. 4F is a plan block diagram of the embodiment of FIG. 4E;

FIG. 4G is a perspective block diagram showing a fourth embodiment foran electrode assembly, according to the present invention;

FIG. 4H is a plan block diagram of the embodiment of FIG. 4G;

FIG. 4I is a perspective block diagram showing a fifth embodiment for anelectrode assembly, according to the present invention;

FIG. 4J is a detailed cross-sectional view of a portion of theembodiment of FIG. 4I;

FIG. 4K is a detailed cross-sectional view of a portion of analternative to the embodiment of FIG. 4I.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 2A and 2B depict an electro-kinetic air transporter-conditionersystem 100 whose housing 102 includes preferably rear-located intakevents or louvers 104 and preferably front and side-located exhaust vents106, and a base pedestal 108. Internal to the transporter housing is anion generating unit 160, preferably powered by an AC:DC power supplythat is energizable using switch S1. Ion generating unit 160 isself-contained in that other than ambient air, nothing is required frombeyond the transporter housing, save external operating potential, foroperation of the present invention.

The upper surface of housing 102 includes a user-liftable handle 112 towhich is affixed an electrode assembly 220 that comprises a first array230 of electrodes 232 and a second array 240 of electrodes 242. Thefirst and second arrays of electrodes are coupled in series between theoutput terminals of ion generating unit 160, as best seen in FIG. 3. Theability to lift handle 112 provides ready access to the electrodescomprising the electrode assembly, for purposes of cleaning and, ifnecessary, replacement.

The general shape of the invention shown in FIGS. 2A and 2B is notcritical. The top-to-bottom height of the preferred embodiment isperhaps 1 m, with a left-to-right width of perhaps 15 cm, and afront-to-back depth of perhaps 10 cm, although other dimensions andshapes may of course be used. A louvered construction provides ampleinlet and outlet venting in an economical housing configuration. Thereneed be no real distinction between vents 104 and 106, except theirlocation relative to the second array electrodes, and indeed a commonvent could be used. These vents serve to ensure that an adequate flow ofambient air may be drawn into or made available to the presentinvention, and that an adequate flow of ionized air that includes safeamounts of O₃ flows out from unit 130.

As will be described, when unit 100 is energized with S1, high voltageoutput by ion generator 160 produces ions at the first electrode array,which ions are attracted to the second electrode array. The movement ofthe ions in an “IN” to “OUT” direction carries with them air molecules,thus electrokinetically producing an outflow of ionized air. The “IN”notion in FIGS. 2A and 2B denote the intake of ambient air withparticulate matter 60. The “OUT” notation in the figures denotes theoutflow of cleaned air substantially devoid of the particulate matter,which adheres electrostatically to the surface of the second arrayelectrodes. In the process of generating the ionized air flow, safeamounts of ozone (O₃) are beneficially produced. It may be desired toprovide the inner surface of housing 102 with an electrostatic shield toreduce detectable electromagnetic radiation. For example, a metal shieldcould be disposed within the housing, or portions of the interior of thehousing could be coated with a metallic paint to reduce such radiation.

As best seen in FIG. 3, ion generating unit 160 includes a high voltagegenerator unit 170 and circuitry 180 for converting raw alternatingvoltage (e.g., 117 VAC) into direct current (“DC”) voltage. Circuitry180 preferably includes circuitry controlling the shape and/or dutycycle of the generator unit output voltage (which control is alteredwith user switch S2). Circuitry 180 preferably also includes a pulsemode component, coupled to switch S3, to temporarily provide a burst ofincreased output ozone. Circuitry 180 can also include a timer circuitand a visual indicator such as a light emitting diode (“LED”). The LEDor other indicator (including, if desired, audible indicator) signalswhen ion generation is occurring. The timer can automatically haltgeneration of ions and/or ozone after some predetermined time, e.g., 30minutes, indicator(s), and/or audible indicator(s).

As shown in FIG. 3, high voltage generator unit 170 preferably comprisesa low voltage oscillator circuit 190 of perhaps 20 KHz frequency, thatoutputs low voltage pulses to an electronic switch 200, e.g., athyristor or the like. Switch 200 switchably couples the low voltagepulses to the input winding of a step-up transformer T1. The secondarywinding of T1 is coupled to a high voltage multiplier circuit 210 thatoutputs high voltage pulses. Preferably the circuitry and componentscomprising high voltage pulse generator 170 and circuit 180 arefabricated on a printed circuit board that is mounted within housing102. If desired, external audio input (e.g., from a stereo tuner) couldbe suitably coupled to oscillator 190 to acoustically modulate thekinetic airflow produced by unit 160. The result would be anelectrostatic loudspeaker, whose output air flow is audible to the humanear in accordance with the audio input signal. Further, the output airstream would still include ions and ozone.

Output pulses from high voltage generator 170 preferably are at least 10KV peak-to-peak with an effective DC offset of perhaps half thepeak-to-peak voltage, and have a frequency of perhaps 20 KHz. The pulsetrain output preferably has a duty cycle of perhaps 10%, which willpromote battery lifetime. Of course, different peak-peak amplitudes, DCoffsets, pulse train waveshapes, duty cycle, and/or repetitionfrequencies may instead be used. Indeed, a 100% pulse train (e.g., anessentially DC high voltage) may be used, albeit with shorter batterylife-time. Thus, generator unit 170 may (but need not) be referred to asa high voltage pulse generator.

Frequency of oscillation is not especially critical but frequency of atleast about 20 KHz is preferred as being inaudible to humans. If petswill be in the same room as the present invention, it may be desired toutilize an even higher operating frequency, to prevent pet discomfortand/or howling by the pet.

The output from high voltage pulse generator unit 170 is coupled to anelectrode assembly 220 that comprises a first electrode array 230 and asecond electrode array 240. Unit 170 functions as a DC:DC high voltagegenerator, and could be implemented using other circuitry and/ortechniques to output high voltage pulses that are input to electrodeassembly 220.

In the embodiment of FIG. 3, the positive output terminal of unit 170 iscoupled to first electrode array 230, and the negative output terminalis coupled to second electrode array 240. This coupling polarity hasbeen found to work well, including minimizing unwanted audible electrodevibration or hum. An electrostatic flow of air is created, going fromthe first electrode array towards the second electrode array. (This flowis denoted “OUT” in the figures.) Accordingly electrode assembly 220 ismounted within transporter system 100 such that second electrode array240 is closer to the OUT vents and first electrode array 230 is closerto the IN vents.

When voltage or pulses from high voltage pulse generator 170 are coupledacross first and second electrode arrays 230 and 240, it is believedthat a plasma-like field is created surrounding electrodes 232 in firstarray 230. This electric field ionizes the ambient air between the firstand second electrode arrays and establishes an “OUT” airflow that movestowards the second array. It is understood that the IN flow enters viavent(s) 104, and that the OUT flow exits via vent(s) 106.

It is believed that ozone and ions are generated simultaneously by thefirst array electrode(s) 232, essentially as a function of the potentialfrom generator 170 coupled to the first array. Ozone generation may beincreased or decreased by increasing or decreasing the potential at thefirst array. Coupling an opposite polarity potential to the second arrayelectrode(s) 242 essentially accelerates the motion of ions generated atthe first array, producing the air flow denoted as “OUT” in the figures.As the ions move toward the second array, it is believed that they pushor move air molecules toward the second array. The relative velocity ofthis motion may be increased by decreasing the potential at the secondarray relative to the potential at the first array.

For example, if +10 KV were applied to the first array electrode(s), andno potential were applied to the second array electrode(s), a cloud ofions (whose net charge is positive) would form adjacent the firstelectrode array. Further, the relatively high 10 KV potential wouldgenerate substantial ozone. By coupling a relatively negative potentialto the second array electrode(s), the velocity of the air mass moved bythe net emitted ions increases, as momentum of the moving ions isconserved.

On the other hand, if it were desired to maintain the same effectiveoutflow (OUT) velocity but to generate less ozone, the exemplary 10 KVpotential could be divided between the electrode arrays. For example,generator 170 could provide +4 KV (or some other fraction) to the firstarray electrode(s) and −6 KV (or some other fraction) to the secondarray electrode(s). In this example, it is understood that the +4 KV andthe −6 KV are measured relative to ground. Understandably it is desiredthat the present invention operate to output safe amounts of ozone.Accordingly, the high voltage is preferably fractionalized with about +4KV applied to the first array electrode(s) and about −6 KV applied tothe second array electrodes.

As noted, outflow (OUT) preferably includes safe amounts of O₃ that candestroy or at least substantially alter bacteria, germs, and otherliving (or quasi-living) matter subjected to the outflow. Thus, whenswitch S1 is closed and B1 has sufficient operating potential, pulsesfrom high voltage pulse generator unit 170 create an outflow (OUT) ofionized air and O₃. When S1 is closed, LED will visually signal whenionization is occurring.

Preferably operating parameters of the present invention are set duringmanufacture and are not user-adjustable. For example, increasing thepeak-to-peak output voltage and/or duty cycle in the high voltage pulsesgenerated by unit 170 can increase air flowrate, ion content, and ozonecontent. In the preferred embodiment, output flowrate is about 200feet/minute, ion content is about 2,000,000/cc and ozone content isabout 40 ppb (over ambient) to perhaps 2,000 ppb (over ambient).Decreasing the R2/R1 ratio below about 20:1 will decrease flow rate, aswill decreasing the peak-to-peak voltage and/or duty cycle of the highvoltage pulses coupled between the first and second electrode arrays.

In practice, unit 100 is placed in a room and connected to anappropriate source of operating potential, typically 117 VAC. With S1energized, ionization unit 160 emits ionized air and preferably someozone (O₃) via outlet vents 150. The air flow, coupled with the ions andozone freshens the air in the room, and the ozone can beneficiallydestroy or at least diminish the undesired effects of certain odors,bacteria, germs, and the like. The air flow is indeedelectro-kinetically produced, in that there are no intentionally movingparts within the present invention. (As noted, some mechanical vibrationmay occur within the electrodes.) As will be described with respect toFIG. 4A, it is desirable that the present invention actually output anet surplus of negative ions, as these ions are deemed more beneficialto health than are positive ions.

Having described various aspects of the invention in general, preferredembodiments of electrode assembly 220 will now be described. In thevarious embodiments, electrode assembly 220 will comprise a first array230 of at least one electrode 232, and will further comprise a secondarray 240 of preferably at least one electrode 242. Understandablymaterial(s) for electrodes 232 and 242 should conduct electricity, beresilient to corrosive effects from the application of high voltage, yetbe strong enough to be cleaned.

In the various electrode assemblies to be described herein, electrode(s)232 in the first electrode array 230 are preferably fabricated fromtungsten. Tungsten is sufficiently robust to withstand cleaning, has ahigh melting point to retard breakdown due to ionization, and has arough exterior surface that seems to promote efficient ionization. Onthe other hand, electrodes 242 preferably will have a highly polishedexterior surface to minimize unwanted point-to-point radiation. As such,electrodes 242 preferably are fabricated from stainless steel, brass,among other materials. The polished surface of electrodes 232 alsopromotes ease of electrode cleaning.

In contrast to the prior art electrodes disclosed by Lee, electrodes 232and 242 according to the present invention are lightweight, easy tofabricate, and lend themselves to mass production. Further, electrodes232 and 242 described herein promote more efficient generation ofionized air, and production of safe amounts of ozone, O₃.

In the present invention, a high voltage pulse generator 170 is coupledbetween the first electrode array 230 and the second electrode array240. The high voltage pulses produce a flow of ionized air that travelsin the direction from the first array towards the second array(indicated herein by hollow arrows denoted “OUT”). As such, electrode(s)232 may be referred to as an emitting electrode, and electrodes 242 maybe referred to as collector electrodes. This outflow advantageouslycontains safe amounts of O₃, and exits the present invention fromvent(s) 106.

According to the present invention, it is preferred that the positiveoutput terminal or port of the high voltage pulse generator be coupledto electrodes 232, and that the negative output terminal or port becoupled to electrodes 242. It is believed that the net polarity of theemitted ions is positive, e.g., more positive ions than negative ionsare emitted. In any event, the preferred electrode assembly electricalcoupling minimizes audible hum from electrodes 232 contrasted withreverse polarity (e.g., interchanging the positive and negative outputport connections).

However, while generation of positive ions is conductive to a relativelysilent air flow, from a health standpoint, it is desired that the outputair flow be richer in negative ions, not positive ions. It is noted thatin some embodiments, however, one port (preferably the negative port) ofthe high voltage pulse generator may in fact be the ambient air. Thus,electrodes in the second array need not be connected to the high voltagepulse generator using wire. Nonetheless, there will be an “effectiveconnection” between the second array electrodes and one output port ofthe high voltage pulse generator, in this instance, via ambient air.

Turning now to the embodiments of FIGS. 4A and 4B, electrode assembly220 comprises a first array 230 of wire electrodes 232, and a secondarray 240 of generally “U”-shaped electrodes 242. In preferredembodiments, the number N1 of electrodes comprising the first array willpreferably differ by one relative to the number N2 of electrodescomprising the second array. In many of the embodiments shown, N2>N1.However, if desired, in FIG. 4A, additional first electrodes 232 couldbe added at the out ends of array 230 such that N1>N2, e.g., fiveelectrodes 232 compared to four electrodes 242.

Electrodes 232 are preferably lengths of tungsten wire, whereaselectrodes 242 are formed from sheet metal, preferably stainless steel,although brass or other sheet metal could be used. The sheet metal isreadily formed to define side regions 244 and bulbous nose region 246for hollow elongated “U” shaped electrodes 242. While FIG. 4A depictsfour electrodes 242 in second array 240 and three electrodes 232 infirst array 230, as noted, other numbers of electrodes in each arraycould be used, preferably retaining a symmetrically staggeredconfiguration as shown. It is seen in FIG. 4A that while particulatematter 60 is present in the incoming (IN) air, the outflow (OUT) air issubstantially devoid of particulate matter, which adheres to thepreferably large surface area provided by the second array electrodes(see FIG. 4B).

As best seen in FIG. 4B, the spaced-apart configuration between thearrays is staggered such that each first array electrode 232 issubstantially equidistant from two second array electrodes 242. Thissymmetrical staggering has been found to be an especially efficientelectrode placement. Preferably the staggering geometry is symmetricalin that adjacent electrodes 232 or adjacent electrodes 242 are spacedapart a constant distance, Y1 and Y2 respectively. However, anon-symmetrical configuration could also be used, although ion emissionand air flow would likely be diminished. Also, it is understood that thenumber of electrodes 232 and 242 may differ from what is shown.

In FIG. 4A, typically dimensions are as follows: diameter of electrodes232 is about 0.08 mm, distances Y1 and Y2 are each about 16 mm, distanceX1 is about 16 mm, distance L is about 20 mm, and electrode heights Z1and Z2 are each about 1 m. The width W of electrodes 242 is preferablyabout 4 mm, and the thickness of the material from which electrodes 242are formed is about 0.5 mm. Of course other dimensions and shapes couldbe used. It is preferred that electrodes 232 be small in diameter tohelp establish a desired high voltage field. On the other hand, it isdesired that electrodes 232 (as well as electrodes 242) be sufficientlyrobust to withstand occasional cleaning.

Electrodes 232 in first array 230 are coupled by a conductor 234 to afirst (preferably positive) output port of high voltage pulse generator170, and electrodes 242 in second array 240 are coupled by a conductor244 to a second (preferably negative) output port of generator 170. Itis relatively unimportant where on the various electrodes electricalconnection is made to conductors 234 or 244. Thus, by way of exampleFIG. 4B depicts conductor 244 making connection with some electrodes 242internal to bulbous end 246, while other electrodes 242 make electricalconnection to conductor 244 elsewhere on the electrode. Electricalconnection to the various electrodes 242 could also be made on theelectrode external surface providing no substantial impairment of theoutflow airstream results.

To facilitate removing the electrode assembly from unit 100 (as shown inFIG. 2B), it is preferred that the lower end of the various electrodesfit against mating portions of wire or other conductors 234 or 244. Forexample, “cup-like” members can be affixed to wires 234 and 244 intowhich the free ends of the various electrodes fit when electrode array220 is inserted completely into housing 102 of unit 100.

The ratio of the effective electric field emanating area of electrode232 to the nearest effective area of electrodes 242 is at least about15:1, and preferably is at least 20:1. Thus, in the embodiment of FIG.4A and FIG. 4B, the ratio R2/R1≈2 mm/0.04 mm≈50:1.

In this and the other embodiments to be described herein, ionizationappears to occur at the smaller electrode(s) 232 in the first electrodearray 230, with ozone production occurring as a function of high voltagearcing. For example, increasing the peak-to-peak voltage amplitudeand/or duty cycle of the pulses from the high voltage pulse generator170 can increase ozone content in the output flow of ionized air. Ifdesired, user-control S2 can be used to somewhat vary ozone content byvarying (in a safe manner) amplitude and/or duty cycle. Specificcircuitry for achieving such control is known in the art and need not bedescribed in detail herein.

Note the inclusion in FIGS. 4A and 4B of at least one output controllingelectrode 243, preferably electrically coupled to the same potential asthe second array electrodes. Electrode 243 preferably defines a pointedshape in side profile, e.g., a triangle. The sharp point on electrode(s)243 causes generation of substantial negative ions (since the electrodeis coupled to relatively negative high potential). These negative ionsneutralize excess positive ions otherwise present in the output airflow, such that the OUT flow has a net negative charge. Electrode(s) 243preferably are stainless steel, copper, or other conductor, and areperhaps 20 mm high and about 12 mm wide at the base.

Another advantage of including pointed electrodes 243 is that they maybe stationarily mounted within the housing of unit 100, and thus are notreadily reached by human hands when cleaning the unit. Were itotherwise, the sharp point on electrode(s) 243 could easily cause cuts.The inclusion of one electrode 243 has been found sufficient to providea sufficient number of output negative ions, but more such electrodesmay be included.

In the embodiment of FIGS. 4A and 4C, each “U”-shaped electrode 242 hastwo trailing edges that promote efficient kinetic transport of theoutflow of ionized air and O₃. Note the inclusion on at least oneportion of a trailing edge of a pointed electrode region 243′. Electroderegion 243′ helps promote output of negative ions, in the same fashionas was described with respect to FIGS. 4A and 4B. Note, however, thehigher likelihood of a user cutting himself or herself when wipingelectrodes 242 with a cloth or the like to remove particulate matterdeposited thereon. In FIG. 4C and the figures to follow, the particulatematter is omitted for ease of illustration. However, from what was shownin FIGS. 2A-4B, particulate matter will be present in the incoming air,and will be substantially absent from the outgoing air. As has beendescribed, particulate matter 60 typically will be electrostaticallyprecipitated upon the surface area of electrodes 242.

Note that the embodiments of FIGS. 4C and 4D depict somewhat truncatedversions of electrodes 242. Whereas dimension L in the embodiment ofFIGS. 4A and 4B was about 20 mm, in FIGS. 4C and 4D, L has beenshortened to about 8 mm. Other dimensions in FIG. 4C preferably aresimilar to those stated for FIGS. 4A and 4B. In FIGS. 4C and 4D, theinclusion of point-like regions 246 on the trailing edge of electrodes242 seems to promote more efficient generation of ionized air flow. Itwill be appreciated that the configuration of second electrode array 240in FIG. 4C can be more robust than the configuration of FIGS. 4A and 4B,by virtue of the shorter trailing edge geometry. As noted earlier, asymmetrical staggered geometry for the first and second electrode arraysis preferred for the configuration of FIG. 4C.

In the embodiment of FIG. 4D, the outermost second electrodes, denoted242-1 and 242-2, have substantially no outermost trailing edges.Dimension L in FIG. 4D is preferably about 3 mm, and other dimensionsmay be as stated for the configuration of FIGS. 4A and 4B. Again, theR2/R1 ratio for the embodiment of FIG. 4D preferably exceeds about 20:1.

FIGS. 4E and 4F depict another embodiment of electrode assembly 220, inwhich the first electrode array comprises a single wire electrode 232,and the second electrode array comprises a single pair of curved“L”-shaped electrodes 242, in cross-section. Typical dimensions, wheredifferent than what has been stated for earlier-described embodiments,are X1≈12 mm, Y1≈6 mm, Y2≈5 mm, and L1≈3 mm. The effective R2/R1 ratiois again greater than about 20:1. The fewer electrodes comprisingassembly 220 in FIGS. 4E and 4F promote economy of construction, andease of cleaning, although more than one electrode 232, and more thantwo electrodes 242 could of course be employed. This embodiment againincorporates the staggered symmetry described earlier, in whichelectrode 232 is equidistant from two electrodes 242.

FIGS. 4G and 4H show yet another embodiment for electrode assembly 220.In this embodiment, first electrode array 230 is a length of wire 232,while the second electrode array 240 comprises a pair of rod or columnarelectrodes 242. As in embodiments described earlier herein, it ispreferred that electrode 232 be symmetrically equidistant fromelectrodes 242. Wire electrode 232 is preferably perhaps 0.08 mmtungsten, whereas columnar electrodes 242 are perhaps 2 mm diameterstainless steel. Thus, in this embodiment the R2/R1 ratio is about 25:1.Other dimensions may be similar to other configurations, e.g., FIGS. 4E,4F. Of course electrode assembly 220 may comprise more than oneelectrode 232, and more than two electrodes 242.

An especially preferred embodiment is shown in FIG. 4I and FIG. 4J. Inthese figures, the first electrode assembly comprises a single pin-likeelement 232 disposed coaxially with a second electrode array thatcomprises a single ring-like electrode 242 having a rounded inneropening 246. However, as indicated by phantom elements 232′, 242′,electrode assembly 220 may comprise a plurality of such pin-like andring-like elements. Preferably electrode 232 is tungsten, and electrode242 is stainless steel.

Typical dimensions for the embodiment of FIG. 4I and FIG. 4J are L1≈10mm, X1≈9.5 mm, T≈0.5 mm, and the diameter of opening 246 is about 12 mm.Dimension L1 preferably is sufficiently long that upstream portions ofelectrode 232 (e.g., portions to the left in FIG. 4I) do not interferewith the electrical field between electrode 232 and the collectorelectrode 242. However, as shown in FIG. 4J, the effect R2/R1 ratio isgoverned by the tip geometry of electrode 232. Again, in the preferredembodiment, this ratio exceeds about 20:1. Lines drawn in phantom inFIG. 4J depict theoretical electric force field lines, emanating fromemitter electrode 232, and terminating on the curved surface ofcollector electrode 246. Preferably the bulk of the field emanateswithin about ±45° of coaxial axis between electrode 232 and electrode242. On the other hand, if the opening in electrode 242 and/or electrode232 and 242 geometry is such that too narrow an angle about the coaxialaxis exists, air flow will be unduly restricted.

One advantage of the ring-pin electrode assembly configuration shown inFIG. 4I is that the flat regions of ring-like electrode 242 providesufficient surface area to which particulate matter 60 entrained in themoving air stream can attach, yet be readily cleaned.

Further, the ring-pin configuration advantageously generates more ozonethan prior art configurations, or the configurations of FIGS. 4A-4H. Forexample, whereas the configurations of FIGS. 4A-4H may generate perhaps50 ppb ozone, the configuration of FIG. 4I can generate about 2,000 ppbozone.

Nonetheless it will be appreciated that applicants' first array pinelectrodes may be utilized with the second array electrodes of FIGS.4A-4H. Further, applicants' second array ring electrodes may be utilizedwith the first array electrodes of FIGS. 4A-4H. For example, inmodifications of the embodiments of FIGS. 4A-4H, each wire or columnarelectrode 232 is replaced by a column of electrically series-connectedpin electrodes (e.g., as shown in FIGS. 4I-4K), while retaining thesecond electrode arrays as depicted in these figures. By the same token,in other modifications of the embodiments of FIGS. 4A-4H, the firstarray electrodes can remain as depicted, but each of the second arrayelectrodes 242 is replaced by a column of electrically series-connectedring electrodes (e.g., as shown in FIGS. 4I-4K).

In FIG. 4J, a detailed cross-sectional view of the central portion ofelectrode 242 in FIG. 4I is shown. As best seen in FIG. 4J, curvedregion 246 adjacent the central opening in electrode 242 appears toprovide an acceptably large surface area to which many ionization pathsfrom the distal tip of electrode 232 have substantially equal pathlength. Thus, while the distal tip (or emitting tip) of electrode 232 isadvantageously small to concentrate the electric field between theelectrode arrays, the adjacent regions of electrode 242 preferablyprovide many equidistant interelectrode array paths. A high exitflowrate of perhaps 90 feet/minute and 2,000 ppb range ozone emissionattainable with this configuration confirm a high operating efficiency.

In FIG. 4K, one or more electrodes 232 is replaced by a conductive block232″ of carbon fibers, the block having a distal surface in whichprojecting fibers 233-1, . . . 233-N take on the appearance of a “bed ofnails”. The projecting fibers can each act as an emitting electrode andprovide a plurality of emitting surfaces. Over a period of time, some orall of the electrodes will literally be consumed, whereupon graphiteblock 232″ will be replaced. Materials other than graphite may be usedfor block 232″ providing the material has a surface with projectingconductive fibers such as 233-N.

As described, the net output of ions is influenced by placing a biaselement (e.g., element 243) near the output stream and preferably nearthe downstream side of the second array electrodes. If no ion outputwere desired, such an element could achieve substantial neutralization.It will also be appreciated that the present invention could be adjustedto produce ions without producing ozone, if desired.

Modifications and variations may be made to the disclosed embodimentswithout departing from the subject and spirit of the invention asdefined by the following claims.

1. An air conditioner system, comprising: an upstanding, elongatedhousing having a top surface, an inlet and an outlet; and an iongenerating unit positioned in said housing, including: a firstelectrode; a second electrode; and a high voltage generator thatprovides a potential difference between said first electrode and saidsecond electrode; wherein said second electrode is removable, throughsaid top surface of said housing, from a resting position within saidhousing to a location external to the housing, to thereby allow saidsecond electrode to be cleaned; and wherein said second electrode isreturnable through said top surface of the housing such that gravitywill assist with return of the second electrode to the resting positionwithin said housing.
 2. The system as recited in claim 1, wherein saidtop surface of said housing further includes a user control.
 3. Thesystem as recited in claim 1, wherein said first electrode is locatedproximate to the inlet, and the second removable electrode is locatedcloser to the outlet than said first electrode.
 4. The system as recitedin claim 1, wherein a user-liftable handle is attached to said secondremovable electrode, said use-liftable handle accessible through anopening in said top surface of said housing.
 5. The system as recited inclaim 1, wherein said second removable electrode is elongated along adirection of said elongated housing.
 6. An air conditioner system,comprising: an upstanding, elongated housing having a top surface, anair inlet vent, and an air outlet vent; an ion generating unitpositioned in said housing, for creating an airflow from said inlet ventto said outlet vent, including: a first emitter electrode; a secondremovable collector electrode, elongated along the direction ofelongation of said housing, and removable through an opening in the topsurface of said housing; and a user-liftable handle secured to saidsecond removable collector electrode, said handle accessible throughsaid opening in said top surface of said housing, to assist a user withlifting said second removable collector electrode out of said housingfrom a resting position within said housing; and wherein said secondremovable electrode is returnable through said opening in said topsurface of said housing such that gravity will assist with return ofsaid second removable collector electrode to the resting position withinsaid housing.
 7. The system as recited in claim 6, wherein said secondremovable collector electrode is hollow.
 8. The system as recited inclaim 6, wherein said second removable collector electrode is“U”-shaped.
 9. The system as recited in claim 6, wherein said secondremovable collector electrode is located proximate to said air outletvent.
 10. The system of claim 6, further comprising: a user operablecontrol located on said top surface of said housing.
 11. An ionproducing system, comprising: a housing that is vertically elongated,said housing including at least one vent; an emitter electrode withinsaid housing; a collector electrode that is vertically elongated when ina resting position within said housing; a high voltage generator toprovide a potential difference between said emitter electrode and saidcollector electrode when said collector electrode is in the restingposition within said housing; and a handle secured to said collectorelectrode, said handle to assist a user with vertically lifting saidcollector electrode out of said housing; wherein said collectorelectrode is vertically returnable with the assistance of gravity,through an opening in an upper portion of said housing, to the restingposition within said housing.
 12. The system of claim 11, furthercomprising: an opening in a top of said housing; and wherein said handleassists a user with vertically lifting said collector electrode outthrough said opening in said top of said housing.
 13. The system ofclaim 11, wherein the high voltage generator comprises a first terminalat a first potential and a second terminal at a second potential thatenable the high voltage generator to provide the potential differencebetween said emitter electrode and said collector electrode; and whereina lower end of said collector electrode mates with said second terminalwhen in the resting position within said housing; and wherein saidcollector electrode disengages from said second terminal when verticallylifted out of said housing.
 14. The system of claim 13, wherein gravitycauses said lower end of said collector electrode to mate with saidsecond terminal when said collector electrode is in the resting positionwithin said housing.
 15. An ion producing system, comprising: anupstanding, elongated housing having a top surface, an inlet and anoutlet; and an ion generating unit positioned in said housing,including: a first electrode; a second electrode; and a high voltagegenerator that provides a potential difference between said firstelectrode and said second electrode; wherein said second electrode isremovable, through said top surface of said housing, from a restingposition within said housing to a location external to the housing, tothereby allow said second electrode to be cleaned; and wherein saidsecond electrode is returnable through said top surface of the housingsuch that gravity will assist with return of the second electrode to theresting position within said housing.
 16. An ion producing system,comprising: an upstanding, elongated housing having an inlet and anoutlet; and an ion generating unit positioned in said housing,including: a first electrode; a second electrode; and a high voltagegenerator that provides a potential difference between said firstelectrode and said second electrode; wherein said second electrode isvertically removable, through an opening in an upper portion of saidhousing, from a resting position within said housing to a locationexternal to the housing, to thereby allow said second electrode to becleaned; and wherein said second electrode is vertically returnablethrough said opening such that gravity will assist with return of thesecond electrode to the resting position within said housing.
 17. An ionproducing system, comprising: an upstanding, vertically elongatedhousing having at least one air vent; an ion generating unit positionedin said housing, including: a first emitter electrode; a secondremovable collector electrode, elongated along a direction of elongationof said vertically elongated housing, and vertically removable throughan opening through a top portion of said housing; and a handle securedto said second removable collector electrode, said handle accessiblethrough said opening to assist a user with vertically lifting saidsecond removable collector electrode out of said housing from a restingposition within said housing; and wherein said second removableelectrode is vertically returnable through said opening such thatgravity will assist with return of said second removable collectorelectrode to the resting position within said housing.
 18. An ionproducing air conditioning system, comprising: an upstanding, verticallyelongated housing having at least one air vent; an ion generating unitpositioned in said housing, including: an emitter electrode; a removablecollector electrode, elongated along a direction of elongation of saidvertically elongated housing, and vertically removable through anopening through a top portion of said housing such that a user canvertically lift said removable collector electrode out of said housingfrom a resting position within said housing; and wherein said removableelectrode is vertically returnable through said opening such thatgravity will assist with return of said removable collector electrode tothe resting position within said housing.
 19. An ion producing system,comprising: an upstanding, vertically elongated housing containing anion generating unit; at least one air vent in said housing; the iongenerating unit including: an emitter electrode; a removable collectorelectrode elongated along a direction of elongation of said verticallyelongated housing when in a resting position within said housing; and ahandle attached to said removable collector electrode such that saidhandle extends in an upward direction from said collector electrode andisolates said ion generating unit from a user when said removablecollector electrode is in the resting position within said housing;wherein said handle is adapted to assist a user with vertically liftingsaid removable collector electrode out of said housing from the restingposition within said housing; and wherein said removable collectorelectrode is vertically returnable into said housing such that gravitywill assist with return of said removable collector electrode to theresting position within said housing.
 20. An ion producing system,comprising: an upstanding, vertically elongated housing containing anion generating unit; at least one air vent in said housing; the iongenerating unit including a removable electrode elongated along adirection of elongation of said vertically elongated housing when in aresting position within said housing; and a handle attached to saidremovable electrode such that said handle extends in an upward directionfrom said electrode and isolates said ion generating unit from a userwhen said removable electrode is in the resting position within saidhousing; wherein said handle is adapted to assist a user with verticallylifting said removable electrode out of said housing from the restingposition within said housing; and wherein said removable electrode isvertically returnable into said housing such that gravity will assistwith return of said removable electrode to the resting position withinsaid housing.
 21. An ion producing system, comprising: an upstanding,vertically elongated housing containing an ion generating unit; at leastone air vent in said housing; the ion generating unit including: anemitter electrode; a removable collector electrode elongated along adirection of elongation of said vertically elongated housing when in aresting position within said housing; and a handle attached to saidcollector electrode such that said handle extends in an upward directionfrom said collector electrode and isolates said ion generating unit froma user, when said collector electrode is in the resting position withinsaid housing; wherein said handle is adapted to assist a user withvertically lifting said removable collector electrode out of saidhousing from the resting position within said housing; and wherein saidremovable collector electrode is vertically returnable into said housingsuch that gravity will assist with return of the second electrode to theresting position within the housing.
 22. An ion producing system,comprising: an upstanding, vertically elongated housing containing anion generating unit; the ion generating unit including a removableelectrode elongated along a direction of elongation of said verticallyelongated housing when in a resting position within said housing; and ahandle attached to said removable electrode such that said handleextends in an upward direction from said electrode and isolates said iongenerating unit from a user, when said removable electrode is in theresting position within said housing; wherein said handle is adapted toassist a user with vertically lifting said removable electrode out ofsaid housing from the resting position within said housing; and whereinsaid removable electrode is vertically returnable into said housing suchthat gravity will assist with return of the second electrode to theresting position within the housing.
 23. An ion producing system,comprising: an upstanding, vertically elongated housing containing anion generating unit; a high voltage generator that provides a potentialdifference in the ion generating unit; the ion generating unit includinga removable electrode elongated along a direction of elongation of saidvertically elongated housing when in a resting position within saidhousing; and a handle fixedly attached to said removable electrode suchthat said handle extends in an upward direction from said electrode andisolates said ion generating unit from a user, when said removableelectrode is in the resting position within said housing; wherein saidhandle is adapted to assist a user with vertically lifting saidremovable electrode out of said housing from the resting position withinsaid housing; and wherein said removable electrode is verticallyreturnable into said housing such that gravity will assist with returnof the second electrode to the resting position within the housing.